Chegu Vinod wrote:
Hello, 'am sending this updated patch as an attachment (as I was having some issues with my smtp server and git send-email setup). Thanks, Vinod
Subject: [PATCH v2] libvirt support to force convergence of live guest migration
Changes since RFC (i.e. v1) patch : - Incorporated feedback from Jiri Denemark
Looks like you addressed all of Jiri's comments from V1, except for the name of the VIR_MIGRATE_AUTO_CONVERGE flag. But I don't have a better suggestion either.
Busy enterprise workloads hosted on large sized VM's tend to dirty memory faster than the transfer rate achieved via live guest migration. Despite some good recent improvements (& using dedicated 10Gig NICs between hosts) the live migration may NOT converge.
Recently support was added in qemu (version 1.6) to allow a user to choose if they wish to force convergence of their migration via a new migration capability : "auto-converge". This feature allows for qemu to auto-detect lack of convergence and trigger a throttle-down of the VCPUs.
This patch includes the libvirt support needed to trigger this feature. (Testing is in progress)
Signed-off-by: Chegu Vinod <chegu_vinod@hp.com> --- include/libvirt/libvirt.h.in | 1 + src/qemu/qemu_migration.c | 40 ++++++++++++++++++++++++++++++++++++++++ src/qemu/qemu_migration.h | 3 ++- src/qemu/qemu_monitor.c | 2 +- src/qemu/qemu_monitor.h | 1 + tools/virsh-domain.c | 7 +++++++
As mentioned earlier, this needs documented in virsh.pod, similar to the virsh.pod changes Jiri made when introducing the VIR_MIGRATE_COMPRESSED flag in commit ecfff1da. Regards, Jim